Blower outlet damper actuator



Feb. 24, 1959 V A. Ii-'GOETTL 2,87 3. BLOWER OUTLET DAMPER ACTUATOR Filed March 28, 1958 2 Sheets-Sheet 1 as 42 5O 58 54 56 2o 34 as 90 62 60 22 1 1 I 1111 11 11/1 11/1 Ii 4%/ as 28 I619 INVENTOR.

AGENT Feb. 24, 1 959 Filed March 28, 1958 2 Sheets-Sheet 2 'INVENTOR.

AGENT United States Patent BLOWER OUTLET DAMPER ACTUATOR Adam D. Goettl, Phoenix, Ariz.

Application March 28, 1958, Serial No. 724,697

8 Claims. (Cl. 230-114) This invention relates to a blower outlet damper actuator and more particularly to a damper actuator which is operable to throttle the outlet of an evaporative cooler in order to sense the amount of air being delivered by the cooler during adjustment of the damper which controls the amount of air being emitted from the cooler grill.

Dampers at the outlet blowers must be operable toward a closed position against the force of air delivered by the blower. Thus, considerable force must be applied to a pivoted damper in order to pivot it about its axis toward a closed position. Furthermore, such force must be maintained since the force of air acting on the damper must be resisted in order to hold the damper in a give partially or fully closed position.

.It is an object of the invention to provide a blower outlet damper actuator which is powered by the shaft. of the blower thereby obviating the necessity of having a separate motor for remotely operating the damper.

Another object of the invention is to provide a very simple yet powerful blower outlet damper actuator which may be very easily controlled by electrical switches of the push button type.

Another object of the invention is to provide a novel mechanism for utilizing power delivered by a blower shaft to open or close a damper at the outlet of a blower.

Another object of the invention is to' provide a blower outlet damper actuator which may be used to operate dampers at the outlets of various blowers including those in evaporative coolers.

Another object of the invention is to provide ablower outlet damper actuator which is adapted precisely to adjust a blower outlet damper to a desired position and to hold it in such position against force of airbeing expelled by the blower.

Further objectsand advantages of the invention may be apparent from the following specification, appended claims and accompanying drawings in which:

Fig. l is a fragmentary side elevational view of a centrifugal-blower and connected duct showing the blower outlet damper actuator of the present invention in connection therewith.

Fig. 2 is a fragmentary plan view of a blower and connected duct showing the blower outlet damper ac tuator of the present invention connected therewith.

from the line 33 of Fig. 2.

223M393 Patented Feb. 24, 1.959

Fig. 4'is a sectional view taken from the line 4-4 of Fig. 1.

Fig. 5 is an. enlarged fragmentary sectional view taken from the line 55 of Fig. 2 and:

Fig. 6 is a diagrammatic view of the electrical wiring in connection with the blower outlet damper actuator. of the present invention.

As shown in Fig. l of the drawings, a centrifugal blower 10 is provided with an inlet eye 12 and an outlet duct 14. The impeller shaft 16 of the blower 10 carries a conventional centrifugal impeller which is not shown and which forms no part of the present invention.

As shown in Fig. 2 of the drawings, the shaft 16 projects outwardly from the side 11 of the blower 10. Mounted on the shaft 16 is a spool 18 whichis fixed to the shaft 16 by a conventional key 20 and a set screw '22. The spool is provided with discs 24 and 26 which are spaced axially of the shaft. These discs Hand 26 are provided with friction clutch surfaces 28 and 30, respectively, and these surfaces are disposed in opposed face to face relationship with each other.

Alternately engageable with the clutch surfaces 28 and 30 is a roller 32 which is fixed to a shaft 34 rotatably mounted in a shaft housing 36. An enlarged bearing portion 38 of the shaft 34 is provided with an annular groove 40 which is engaged by the end 42 of a bolt screw threaded in the shaft housing 36. This bolt 42 in thegroove 40 limits end play of the shaft 34 with respect to the housing 36.

The housing 34 is provided with a trunnion 44 which projects therefrom in a direction laterally of the axis of the shaft 34. This trunnion extends through a bracket 46 which is stationarily mounted on the side of the blower by means of rivets or other fixtures 48.

Mounted on the bracket 46 are electro magnets or solenoid coils 50 and 52. concentrically movable in 32- may alternately be forced into engagement with the clutch surfaces 28 and 30 of the discs 24 and 26 of the spool 18 whereby the shaft 34 is alternately driven by the roller 32 in different directions.

Connected, by any suitable means, to the end of the shaft 34 is a flexible cable 59 which extends through a conventional flexible sheath 60 which is secured to the end of the shaft housing 36 by a screw threaded nut 62. The opposite end of the cable 59 is provided with a square in cross section stub 64 which is fitted into a conforming socket 66 of a worm pinion 68.. This pinion meshes with a worm gear 70 fixed to a damper shaft 72 which supports a damper 74 in the duct 14. The damper 74 may be pivoted about the axis of the shaft 72, by the worm gear 70, and thereby partially or fully close off flow through the duct 14.

As shown in Fig. 5 of the drawings the cable sheath 60 is secured by a screw threaded nut 76 to a housing 78 in which the worm pinion 68 is rotatably mounted. The housing 78 is provided with an extending portion 80 having a bearing 82 in which the hub 84 of the worm gear 70 is mounted. This arrangement holds a proper operating tolerance between the teeth of the worm pinion 68 and the worm gear 78. The worm gear housing 78 is fixed to the side 86 of the duct 14 by means of screws 88 or other suitable means as desired.

Supported on the bracket 46 is a strap shaped bracket 90 which extends laterally across the shaft housing 36 and resists tipping of the shaft housing 36 when the roller 32 is engaged with one of the clutch surfaces 28 or 30. This'bracket has its opposite ends fixed to the bracket 46and is offset therefrom between its ends to slidingly support the opposite side of the shaft housing from the bracket 46 as shown best in Fig. 3 of the drawings. The strap 9t extends a considerable distance laterally of the shaft housing 36 in order to permit sufficient pivotal movement about the axis of the trunnion 44 so that the roller 32 may be engaged with eitherof the clutch surfaces 28 or 30. Supported in the bracket 99 are centering springs 91 and 93 which engage opposite sides of the shaft housing 36 in order normally to hold the roller 32 in a median position between the clutch surfaces 28 and 30 when neither of the solenoids 50 or 52 is energized.

Coupled to the shaft 72 of the damper 74 is a flexible shaft 92' which is connected to a pointer 94 pivotally mounted with respect to a dial 96 so that a position of the damper 74 may be visually comprehended by viewing the pointer 94 and dial 96. This dial may be located adjacent to switches 98 and 99 which are usable by the operator of the present blower outlet damper actuator. The switches and dial may be located remotely from: the damper 74, as will be hereinafter described in detail.

As shown in Fig. 6 of the drawings the switches 98 and 99 are push button switches and are normally open. Springs 100 and 102 tend to maintain these switches open. A conductor 104 is electrically connected to both switches and when the switch 98 is closed its contacts connect the conductor 104 with a conductor 106 which is coupled to the solenoid coil 50'. The opposite end of the solenoid coil 50 is coupled to the conductor 108 which completes'the circuit to the power source. The switch99 when closed connects the conductor 104 with a' conductor 110 connected to the solenoid coil 52 for energizing it. It will be seen that when the coil 50 is energized the armature 54 will move toward it thereby carrying the yoke 56 and the trunnion 58 toward the coil 50. Alternately the coil 52 may be energized by closing the switch 99 whereupon the armature 54 will move toward the coil 52 and carry thetrunnion 58 in the yoke toward'said coil 52.

It will be noted that a legend Open damper may be disposed adjacent the switch 98 while a legend Closed damper may be disposed adjacent the switch 99. This indicates to the operator that when the switch 98 is closedor when the operator presses on the switch button that the damper'will move toward an open position while pressure'on the button of the switch 99 will move the damper toward a closed position, all as will be hereinafter described in detail. The foregoing legends are not illustrated in the drawing.

Operation of the blower outlet damper actuator of the present invention is substantially, as follows:

When the operator of the blower outlet damper actuator of the present invention wishes to close the damper 74, he presses the push button of the switch 99 which energizes the coil 53?; and moves the armature 54 toward the coil 52. As shown in Fig. 2"of the drawings, movement of the armature 54 toward and into the coil 52 carries the yoke 56 toward the coil 52 and thereby movesthe trunnion 58 of the shaft housing 36 toward the coil 52'. This causes pivotal movement of the roller 32' about theaxis of the trunnion 44 and forces theroller 32'- into engagement with the clutch surface 28 f the disc 24. Since the shaft 16 of the blower is" rotating it rotates the spool 18 and causesr'ot'ation of the" shaft 34 which rotates the flexible shaft 59 in connection with the worm pinion 68. This worm pinion 68 pivots the worm gear 70 which rotates the shaft 72 and pivots the damper '74. During this pivotal movement of the dam er 74 toward" a'closed position the arm Mimi/arses the dial 96 giving the operator a visual indication of the rate and degree to which the damper 74 is responding. Furthermore, the dial 96 and switches 98 and 99 may be in the vicinity of a duct outlet of the blower 10 so that the operator may also feel the reduction of air caused by closing action of the damper 74. 7

When the air flow through the duct 14 has been reduced to a desired amount the operator releases his finger from the button of the switch 99 and the spring 102 forces it open and de-energizes the coil 52 thereby relieving force of the solenoid so that the roller 32 may be forced back to a neutral position by centering springs 91 and 93 acting on the housing 36 and disposed within the bracket 90.

In the neutral position the roller 32 is between the clutch disc surfaces 28 and 30 and does not engage either of them. Thus, a release of the switch button 99 stops closing action of the damper 74. When the push button of the switch 99 is pressed and the solenoid 5% is energized it moves the armature 54 toward the solenoid coil 50 and causes the roller 32 to engage the clutch surface 30 which provides an opposite rotation of the shaft 34 and consequently an opposite rotation of the worm pinion and worm gear thereby forcing the damper74 to move toward an open position. When pressure on the button of the switch 98 is released it opens by force of the spring 100 and the roller 32 is released from the clutch surface 30 by the centering springs 91 and 93 which act upon the housing 36.

When the damper 74 is in a partially closed position and the forced air passing from the blower 10 acts thereon, torque is exerted on the shaft 72 and transmitted to the gear '79. Since it is a worm gear in mesh with the worm pinion 68 it is locked against rotation and thereby maintains the damper 74in a desired adjusted position. v

It'will be obvious to those skilled in the art that various modifieations of the invention may be resorted to in a manner limited only by a just interpretation of the following claims.

I claim:

1. An actuator system for controlling the outlet damp er of a blower comprised of: a blower shaft; a spool carried by said shaft and having opposed facing clutch discs thereon, a roller position between said clutch discs; a second shaft fixed to said roller; a shaft housing rotatably supporting said second shaft and pivotally mounted to swing back and forth between said clutch disc surfaces; a pair of solenoids" disposed to pivotally actuate said second shaft and shaft housing; a flexible shaft coupled carried by said shaft and having opposed facing clutch discs" thereon, a roller positioned between said clutch discs; a' second shaft fixed to said roller; a shaft housing rotatably supporting said second shaft and pivotally mounted to swing back and forth between said clutch disc surfaces; a pair of solenoids disposed to pivotally actuate saidsecond shaft and shaft housing; a flexible shaft coupled to said second shaft, a worm pinion driven by said flexible shaft, a worm gear meshing withsaid worm pinion; and a damper connected to said worm gear and movable tovary the outlet ofsaid blower; electrical switches connected respectively to said solenoids.

3. An actuator system for controlling the-outlet damper of a-blower comprised of: a blower. shaft; a spool carried by said shaft and'having', opposed fac'ingi clutch discs thereon, a roller positioned between said clutch discs; asecond shaft fixed to said roller; a shaft housing" savages disc surfaces; 21 pair of solenoids disposed to pivotally actuate said second shaft and shaft housing; a flexible shaft coupled to said second shaft, a worm pinion driven by said flexible shaft, a worm gear meshing with said worm pinion; and a damper connected to said worm gear and movable to vary the outlet of said blower; electrical switches connected respectively to said solenoids; a common armature extending through both of said solenoids and having a yoke therebetween, a trunnion projecting from said second shaft housing and engageable by said yoke to cause pivotal movement of said second shaft and said second shaft housing.

4. An actuator system for controlling the outlet damper of a blower comprised of: a blower shaft; a spool mounted on said shaft and having opposed inwardly facing clutch surfaces; a roller disposed between said surfaces and engageable therewith, a second shaft for said roller; a housing rotatably supporting said second shaft; stationary means pivotally mounting said housing for lateral pivotal movement relative to said clutch disc surfaces whereby said roller is alternately engageable therewith; means operably connected with said second shaft housing for pivoting it; a worm pinion operable by said second shaft; a worm gear in mesh with said worm pinion; and a damper coupled to said worm gear and disposed to vary the outlet of said blower.

5. An actuator system for controlling the outlet damper of a blower comprised of: a blower shaft; a spool mounted on said shaft and having opposed inwardly facing clutch surfaces; a roller disposed between said surfaces and engageable therewith, a second shaft for said roller; a housing rotatably supporting said second shaft; means pivotally mounting said housing for lateral pivotal' movement relative to said clutch disc surfaces whereby said roller is alternately engageable therewith; a worm pinion operable by said second shaft; a worm gear in mesh with said Worm pinion; and a damper coupled to said worm gear and disposed to vary the outlet of said blower; and stationarily mounted electro magnetic means operably disposed to pivot said second shaft housing.

6. An actuating system for controlling the outlet damper of a blower comprised of: a blower shaft; a spool mounted on said shaft and having opposed inwardly facing clutch surfaces; a roller disposed between said surfaces and engageable therewith, a second shaft for said roller; a housing rotatably supporting said second shaft; means pivotally mounting said housing for lateral pivotal movement relative to said clutch disc surfaces whereby said roller is alternately engageable therewith; a worm pinion operably connected to said second shaft; a worm gear in mesh with said worm pinion; and a damper coupled to said worm gear and disposed to vary the outlet of said blower; and stationarily mounted electro magnetic means operably disposed to pivot said second shaft housing; switch means coupled to said electro magnetic means, said switch means being located remotely therefrom.

7. An actuator system for controlling the outlet damper of a blower comprised of: a blower shaft; a spool carried by said shaft and having opposed facing clutch disc surfaces thereon; a roller positioned between said clutch discs; a second shaft fixed to said roller; shaft bearing means rotatably supporting said second shaft and movable to permit said roller to swing back and forth between said clutch disc surfaces for alternately engaging the same; a pair of solenoids disposed to actuate said second shaft and bearing means to move said roller alternately into contact with said facing clutch disc surfaces; a damper movable to vary the outlet of a blower; and means coupled to said second shaft and disposed to actuate said damper.

8. An actuator system for controlling the outlet damper of a blower comprised of a. blower having a shaft; a spool mounted on said shaft and having opposed inwardly facing clutch surfaces; a roller disposed between said surfaces and engageable therewith; a second shaft for said roller; bearing means for said second shaft disposed movably to support said second shaft and said roller for lateral movement relative to said clutch disc surfaces whereby said roller is alternately engageable therewith; means disposed to move said second shaft and bearing means; a damper disposed to vary the outlet of said blower and means interconnecting said second shaft and said damper whereby rotation of said second shaft caused by engagement of said roller with one of said clutch surfaces actuates said damper to vary the outlet of said blower.

References Cited in the file of this patent UNITED STATES PATENTS 621,551 Worz Mar. 21, 1899 1,522,877 Gibson Jan. 13, 1925 1,956,829 Frank May 1, 1934 1,990,086 Nelson Feb. 5, 1935 

